How to interline curtains is a skill which will give your curtains a professional look and feel.
Interlining can be used in the majority of window treatments, and it's something I nearly always recommend to clients. On a few occasions it isn't necessary, such as for small windows, or when the fabric is very thick. But if you can use it, do so.
It's a simple technique which involves sewing a layer of interlining between the fabric and the lining.
What are the advantages? Go to this page for more details.
First, lay a fabric panel face up on the table. Mark out the position of the hem lines and side turnings with pins. Mark the miter points for the corners with pins if you're using a true miter.
Now lay the panel face down on the table. It's best if you secure the fabric so it can't move (fabric covered bricks are useful).
Place the interlining panel on top so the sides are level with the sides of the fabric panel. The base of the interlining should be 3" (7.5cms) up from the base of the fabric so that it lies on the first hem fold.
Make sure that the interlining is absolutely flat and smooth.
Fold back the interlining and using an interlock stitch secure it every half width and on the seams. Start from the hem and work up, finishing about 4" (10cms) from the top.
Now fold the sides in about 1½" (4cms), fold up the hem and miter the corners. Use a herringbone stitch (catchstitch) to secure the sides to the interlining, and a slip stitch on the hem and corners. Remember to insert weights into the corners and on any joins.
Don't stitch all the way up to the top. Estimate how deep your styling tape (if you'll be machine heading) or buckram (if you'll be hand heading) will be and stop just short of that amount.
The final part of how to interline curtains is attaching the lining. Measure the finished length from the hem and mark the top with pins. Move these to the right side of the fabric. Now trim the interlining to this line of pins.
Starting at the leading edge lay the lining panel with the front uppermost onto the drape. Fold back the lining and interlock it to the interlining on every seam and every half width.
Cut the lining so it's level with the sides of the fabric. Turn it back and under so it's 1" (2.5cms) back from the sides and use a slip stitch to secure it.
Fold over the top of the drape marked out by the pins. You can mock miter the corners using a slip stitch. Fold the lining over about 1/4" (0.6cms) from the top and slip stitch.
Repeat for the other drape, and make sure they are both exactly the same length.
As you can see, when you learn how to interline curtains the process is straightforward. Just take your time, keep all your work neat and tidy, and you're well on the way to producing great drapery!